Jet-stabilized combustion systems, in which the fuel is combusted in a jet flame downstream of the burner, have a simple premix zone in comparison to swirl-stabilized systems. Since the pressure difference in the burner is converted exclusively into the axial velocity component, these burners are distinguished by a lower tendency to flashback, for which reason it is also possible to use this burner for combusting more highly reactive combustion mixtures having a higher hydrogen fraction.
Furthermore, jet-stabilized combustion systems generate no swirl-induced turbulence structures which can cause flame instabilities. Such a jet-stabilized combustion system is disclosed for example in US 2010/0300104 A1. In order to accommodate the premix passages, what is termed a nozzle carrier (also “jet carrier”) is required which, depending on the design, has a different number of nozzles which can be arranged concentrically on one or more rings.
The nozzle carrier is conventionally made of solid forged material which is very expensive but is advantageous for the prototype design since this means it is comparatively simple to produce. Furthermore, no cooling is required on the hot gas side of the nozzle carrier on account of good mechanical properties and good heat transfer between air in the nozzle carrier and the nozzle carrier itself.
Since the nozzle carrier is currently produced by forging using for example a nickel alloy, machining the required bores is onerous, the construction is solid and thus also the weight is high, furthermore the shape of the component is limited by the production method. Consequently, the component is very expensive to manufacture and some component properties cannot be realized. At least, it is very onerous to introduce additional features or particularities, such as cooling air ducts or purge air ducts, into the nozzle carrier.
In addition, mass production cannot be envisaged on account of the costs.